1. Field of the Invention
The subject invention generally relates to a heating, ventilation and air conditioning (HVAC) system of the type including a valve for controlling air flow. More specifically, the HVAC systems include a film valve that is linearly movable for controlling air flow.
2. Description of the Prior Art
These HVAC systems are known in the art for use in automobiles and include a housing that defines an air passage for directing air flow through the housing. A film having edges and openings to allow air to pass through is supported by the housing and serves as an air distribution valve to control the air flow. Frequently, a sprocket is rotatably supported by the housing and has teeth engaging holes in the film to move the film linearly across the air passage. U.S. Pat. No. 6,569,009 exhibits one example of such an HVAC system.
Due to air pressure and vibration, such films frequently float relative to drive mechanisms and negatively affect the engagement between the drive mechanism and the film.